In the article entitled “A Novel Organ Culture Model of Mouse Intervertebral Disc Tissues” [Cells Tissues Organs. 2016;201(1):38–50; DOI: 10.1159/000439268] by Yan et al., the following corrections should be observed.

Following publication, the authors identified an image assembly error in Figure 4b, in which the images for “AF” and “NP” groups were erroneously duplicated with overlapping images from the “NP” and “EP” groups of Figure 4a. The corrected figure is shown below.


In addition, the authors found the figure legend for Figure 5 was not clearly described and would like to revise it. To avoid any confusions, the authors also revised the Methods section “Calcein Staining of the Cultured IVD Samples”.

The authors would also like to clarify the partial overlapping images in some panels of Figure 2b and Figure 3a. Since the field views of the tissue samples were too large to be shown in a single field at high magnifications, images from the three important anatomical parts, AF, NP and EP, of the same samples are shown.

Fig. 5. Efficient and dynamic fluorescent calcein labeling of the cultured IVD tissues. The isolated lumbar IVDs were maintained in 10% FBS medium containing 100 mM calcein, 50 μg/ml ascorbic acid and 1 μM β-glycerophosphate under submersion culture condition (n = 5). At least three independent batches of samples were set up for the culturing and staining experiments. The cultured IVDs were continuously imaged under a bright-field and fluorescence stereomicroscope (Olympus SZX16), and the representative superimposed images at day 7 are shown (a). To document dynamic/accumulative calcein labeling, the cultured IVD tissues in (a) were continuously imaged at day 2 (b), day 5 (c) and day 14 (d) under a fluorescence stereomicroscope. The EPs are indicated by arrows. Representative images were randomly selected from three of the five samples for each time point.

Calcein Staining of the Cultured IVD Samples

The isolated IVD tissues were incubated in DMEM containing 10% FBS, 50 μg/ml ascorbic acid, 1 μM β-glycerophosphate, 100 mg/ml penicillin-streptomycin solution, and 100 mM calcein. At least three independent batches of samples were set up for culturing and staining experiments to ensure reproducibility. The cultured and stained IVDs were continuously imaged under both bright field and fluorescence field by using a fluorescence stereomicroscope (Olympus SZX16, Olympus Corporation of the Americas, Center Valley, PA) at days 2, 5, 7, and 14. Fluorescence imaging settings (i.e., amplification and fluorescence exposure time) were kept at the same values for the fluorescence stereomicroscope throughout the duration of the experiments. At the endpoint (day 14), the cultured and stained IVD samples were also subjected to frozen sectioning and examined under a fluorescence microscope. Superimposed/merged bright field and corresponding fluorescence images were obtained by using the cellSens Imaging Software provided by Olympus.